The present invention is directed to improved tissue expanders, tissue expander systems, and methods for expanding tissue. More particularly, the present invention is directed to non-fluidized tissue expanders and systems that are operative to selectively and controllably expand in a completely self-contained environment without requiring any type of inflation means.
In this regard, tissue expanders are well-known in the art. Exemplary of such tissue expanders include those disclosed in U.S. Pat. No. 5,066,303 to Bark et al.; U.S. Pat. No. 4,671,255 to Dubrul et al.; U.S. Pat. No. 4,662,357, to Pierce et al.; U.S. Pat. No. 4,685,447 to Iversen et al.; and U.S. Pat. No. 4,899,764 to Gauger et al., the teachings of all of which are expressly incorporated by reference.
Essentially, tissue expanders of the prior art comprise an inflatable body, having an inflation valve or button connected thereto, the latter typically being formed upon the inflatable body itself, as described in U.S. Pat. Nos. 4,671,255 and 5,066,303, on one hand, or located remotely and connected to the inflatable body by means of an elongated conduit, as disclosed in U.S. Pat. Nos. 4,899,764 and 4,685,447.
In either embodiment, the inflatable body of the tissue expander is placed subcutaneously within the locus where tissue is to be expanded. The inflation valve is likewise positioned or implanted subcutaneously to allow gradual introduction of fluid, which is typically saline, into the inflation body by injection. After gradual inflation at pre-determined intervals, the skin and subcutaneous tissues overlying the expander are consequently caused to expand in response to the pressure exerted upon such tissues by the inflatable body as solution is gradually introduced there into.
After gradual inflation at pre-determined intervals, which may extend over weeks or months, the skin and subcutaneous tissue will expand to the point where further medical procedures can be performed, such as the permanent implantation of a prosthesis, plastic and reconstructive surgery, or for use of the skin and subcutaneous tissue for use in some other part of the body.
Despite their widespread applicability and extensive utilization, however, most tissue expanders suffer from numerous drawbacks. In this regard, virtually all tissue expanders rely upon an inflatable body requiring incremental quantities of fluid to be introduced therein to thus cause the desired expansion. Because virtually all fluids introduced into inflatable-type tissue expanders must necessarily be administered by injection, the procedure by which such fluids are introduced can be painful and increase the risk of an inadvertent needle stick experience. With respect to the latter, it is well-known that such an experience can lead to the transmission of blood borne diseases, such as hepatitis and HIV.
Moreover, it is well-known that the use of hypodermic needles to deliver fluid frequently results in the inadvertent puncture of the inflatable body of the expander. As a consequence, a leakage is formed in the inflatable body that requires surgical replacement of the tissue expander, which further results in additional surgery, patient discomfort, expense, and increased healing time.
Along these lines, because the delivery of fluid into tissue expanders requires the use of hypodermic needles, such procedure must necessarily be performed by skilled health care workers, which adds significantly to the expense associated with utilizing tissue expanders, as well as inconveniences patients who must routinely make office visits and the like in order to insure proper tissue expansion. Indeed, it is a recognized problem with conventional tissue expanders when attempts we made to expand the inflatable body as rapidly as practical to thus minimize the number of injections (and hence office visits) to be administered. Such practice, however, frequently results in the tissue expander being expanded too rapidly, which can cause substantial pain for the patient and damage the skin and subcutaneous tissues sought to be increased.
As such, there is a substantial need in the art for a tissue expander that can effectively and efficiently expand over time so as to generate an enlarged area of overlying tissue that does not rely upon the infusion of fluids into an inflatable body. More specifically, there is a need for a tissue expander that completely eliminates the need to administer injections or otherwise place the patient and health care worker at increased risk of a needle stick experience in order to introduce fluids to cause expansion of the tissue expander, as per conventional prior art tissue expanders. There is yet further a need in the art for a tissue expander that can be designed according to any of a variety of configurations to thus attain selective and controllable tissue expansion in a manner far superior than prior art tissue expanders. Still further there is a need in the art for such a tissue expander that is of simple construction, may be readily fabricated from existing materials utilizing existing technology, can be utilized for a wide variety of tissue expansion applications, is safe and of relative low cost, can be operated in a very simple manner that may not require procedures involving skilled health care workers, and can be readily implemented for use in virtually all types of procedures requiring tissue expansion.